input: synaptics: defer touch resume to workqueue

During device resume, the touch resume function is called after
display resume. Touch resume function will take about >200ms.
Defer the touch resume function to a workqueue to reduce the total
device resume time. An optional DT property is added to enable this
on targets that need this feature.

Change-Id: Ia9b055144c5a7f29f0f0d57428cccbe15a7d7a87
Signed-off-by: zhaoyuan <yzhao@codeaurora.org>

Documentation/devicetree/bindings/input/touchscreen/synaptics_dsx_i2c.txt

@@ -67,6 +67,7 @@ These properties are defined only when synaptics,detect-device property is defin
  - synaptics,bypass-sensor-coords-check : Bypass the comparison of sensor coordinates
 				range read from DT and touch controller. Used when some
 				touch panels in the field are unprogrammed and misprogrammed.
+ - synaptics,resume-in-workqueue : specifiy whether to defer the resume to workqueue.
 
 Example:
 	i2c@f9927000 {

drivers/input/touchscreen/synaptics_dsx/synaptics_dsx_core.c

@@ -115,6 +115,7 @@ static ssize_t synaptics_rmi4_full_pm_cycle_store(struct device *dev,
 		struct device_attribute *attr, const char *buf, size_t count);
 
 #if defined(CONFIG_FB)
+static void fb_notify_resume_work(struct work_struct *work);
 static int fb_notifier_callback(struct notifier_block *self,
 				unsigned long event, void *data);
 #elif defined(CONFIG_HAS_EARLYSUSPEND)
@@ -3669,6 +3670,7 @@ static int synaptics_rmi4_probe(struct platform_device *pdev)
 	}
 
 #ifdef CONFIG_FB
+	INIT_WORK(&rmi4_data->fb_notify_work, fb_notify_resume_work);
 	rmi4_data->fb_notif.notifier_call = fb_notifier_callback;
 
 	retval = fb_register_client(&rmi4_data->fb_notif);
@@ -3911,6 +3913,13 @@ static int synaptics_rmi4_remove(struct platform_device *pdev)
 }
 
 #if defined(CONFIG_FB)
+static void fb_notify_resume_work(struct work_struct *work)
+{
+	struct synaptics_rmi4_data *rmi4_data =
+		container_of(work, struct synaptics_rmi4_data, fb_notify_work);
+	synaptics_rmi4_resume(&(rmi4_data->input_dev->dev));
+}
+
 static int fb_notifier_callback(struct notifier_block *self,
 				unsigned long event, void *data)
 {
@@ -3920,10 +3929,24 @@ static int fb_notifier_callback(struct notifier_block *self,
 		container_of(self, struct synaptics_rmi4_data, fb_notif);
 
 	if (evdata && evdata->data && rmi4_data) {
-		if (event == FB_EARLY_EVENT_BLANK)
-			synaptics_secure_touch_stop(rmi4_data, 0);
-		else if (event == FB_EVENT_BLANK) {
 		blank = evdata->data;
+		if (rmi4_data->hw_if->board_data->resume_in_workqueue) {
+			if (event == FB_EARLY_EVENT_BLANK) {
+				synaptics_secure_touch_stop(rmi4_data, 0);
+				if (*blank == FB_BLANK_UNBLANK)
+					schedule_work(
+						&(rmi4_data->fb_notify_work));
+			} else if (event == FB_EVENT_BLANK &&
+					*blank == FB_BLANK_POWERDOWN) {
+					flush_work(
+						&(rmi4_data->fb_notify_work));
+					synaptics_rmi4_suspend(
+						&(rmi4_data->input_dev->dev));
+			}
+		} else {
+			if (event == FB_EARLY_EVENT_BLANK) {
+				synaptics_secure_touch_stop(rmi4_data, 0);
+			} else if (event == FB_EVENT_BLANK) {
 				if (*blank == FB_BLANK_UNBLANK)
 					synaptics_rmi4_resume(
 						&(rmi4_data->input_dev->dev));
@@ -3932,6 +3955,7 @@ static int fb_notifier_callback(struct notifier_block *self,
 						&(rmi4_data->input_dev->dev));
 			}
 		}
+	}
 
 	return 0;
 }

drivers/input/touchscreen/synaptics_dsx/synaptics_dsx_core.h

@@ -5,7 +5,7 @@
  *
  * Copyright (C) 2012 Alexandra Chin <alexandra.chin@tw.synaptics.com>
  * Copyright (C) 2012 Scott Lin <scott.lin@tw.synaptics.com>
- * Copyright (c) 2014, The Linux Foundation. All rights reserved.
+ * Copyright (c) 2014, 2016, The Linux Foundation. All rights reserved.
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -248,6 +248,7 @@ struct synaptics_rmi4_data {
 	struct mutex rmi4_reset_mutex;
 	struct mutex rmi4_io_ctrl_mutex;
 #if defined(CONFIG_FB)
+	struct work_struct fb_notify_work;
 	struct notifier_block fb_notif;
 #elif defined(CONFIG_HAS_EARLYSUSPEND)
 	struct early_suspend early_suspend;

drivers/input/touchscreen/synaptics_dsx/synaptics_dsx_i2c.c

@@ -1,7 +1,7 @@
 /*
  * Synaptics DSX touchscreen driver
  *
- * Copyright (c) 2014-2015, The Linux Foundation.  All rights reserved.
+ * Copyright (c) 2014-2016, The Linux Foundation.  All rights reserved.
  *
  * Linux foundation chooses to take subject only to the GPLv2 license terms,
  * and distributes only under these terms.
@@ -320,6 +320,9 @@ static int synaptics_dsx_parse_dt(struct device *dev,
 	rmi4_pdata->bypass_packrat_id_check = of_property_read_bool(np,
 			"synaptics,bypass-packrat-id-check");
 
+	rmi4_pdata->resume_in_workqueue = of_property_read_bool(np,
+			"synaptics,resume-in-workqueue");
+
 	rmi4_pdata->reset_delay_ms = RESET_DELAY;
 	rc = of_property_read_u32(np, "synaptics,reset-delay-ms", &temp_val);
 	if (!rc)

include/linux/input/synaptics_dsx_v2.h

@@ -5,7 +5,7 @@
  *
  * Copyright (C) 2012 Alexandra Chin <alexandra.chin@tw.synaptics.com>
  * Copyright (C) 2012 Scott Lin <scott.lin@tw.synaptics.com>
- * Copyright (c) 2015, The Linux Foundation. All rights reserved.
+ * Copyright (c) 2015-2016, The Linux Foundation. All rights reserved.
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -101,6 +101,7 @@ struct synaptics_dsx_board_data {
 	bool disable_gpios;
 	bool detect_device;
 	bool bypass_packrat_id_check;
+	bool resume_in_workqueue;
 	const char *fw_name;
 };